A variety of digital and analog cameras exist, capable of capturing images in a number of formats including still picture images, sequences of still picture images and video image sequences.
In most instances, a photographer takes a picture after he has looked through a view finder and determined that the image he desires is correctly within the field of view of the camera. The field of view is the area of the scene that will be captured by the camera, either as a still image or a video sequence. If desired, the photographer may zoom in or out of a scene so as to ensure that all of the desired image is within the field of view of the camera.
U.S. Pat. No. 5,752,094, incorporated herein by reference, describes an auto zoom apparatus for a camera. The camera has an inertial motion sensor arranged to detect a displacement of the camera when a switch is operated, with the detected spatial displacement being used to determine the focal length of the zoom lens. The camera zoom is operated by the photographer aiming the centre of the view finder at one corner of a desired image, pressing the button and moving the centre of the view finder to the diagonally opposite corner of the desired image. The zoom of the camera is hence set based upon the motion of the camera, with the intention being to capture the desired image. This type of apparatus is extremely sensitive to errors within the inertial motion sensors used to detect the range of movement of the camera.